Brush holder for dynamo electric machines



- June'l4, 1932. P A. M. M CUTCHEON 1,363,013 BRUSH HOLDER FOR DYNAMO ELECTRIC MACHINES Fi l d April 9, 1951 INVENTOR.

Q/elamc/ek W1 7774: (u fcfiwn A TTORNEYS Patented June 14, 1932 UNITED STATES PATENT OFFICE ALEXANDER MORTON MACCUTCI-IEON, OF SHAKER HEIGHTS, OHIO, ASSIGNOR TO THE RELIANCE ELECTRIC AND ENGINEERING COMPANY, OF CLEVELAND, OHIO, A COR- IOR-AIION OF OHIO BRUSH HOLDER FOR DYNAMO ELECTRIC MACHINES Application filed. April 9,

This invention relates to dynamo electric machines, and more particularly to brush holders for use in motors, generators, and the like; and it is among the objects of the invention to provide a construction in which spring pressure may be maintained upon the brush with an effective and simple mounting of the spring. A further object is the provision of a spring mount which is self-retaining. An-

' other object also is the provision of a comous ways in which the principle of the invention may be employed.

In said annexed drawing Fig. 1 is a plan View showing an embodiment of the invention; Fig. 2 is a side elevational view; and Fig. 3 is a side elevational view of a detail, on slightly enlarged scale.

In the form shown in the drawing, a. brush 2, for instance of carbon composition, is supported against a commutator 3 by means of a holder including a bracket 4: suitably supported at 5 to a stationary part of the machine, the brush riding in a guide-way 6. In

order to press the brush against the commutator, a spring 7 is carried by the brush holder and by means of an extension 8 bears against the brush, thereby urging the same toward the commutator. With a spring of spiral form as illustrated, a convenient mounting comprises a sleeve or quill 9 revolubly or oscillatively set on a stud or pin 10 secured to the bracket at. Such mounting allows of a turning of the quill or sleeve with respect to the stud, as may be involved in the various positioning of the spring-extension 9. suitably formed spring will grip the sleeve or quill sufliciently Without mechanical attachment; however, mechanical attachment 1931. Serial No. 528,771.

by an inset lug from spring-end to quill or other means for positively fastening the spring and quill together may be applied as desired.

Between the sleeve or quill 9 and the bracket 4 an adjustable interengagement or ratchet is provided. In the particular form shown, this embodies a dog or latclrtooth 11 fixed to the bracket 4:, and coacting therewith a series of ratchet teeth 12 on the inner end of the quill 9. The number of the teeth may vary, depending upon the size of the installation; and the fineness of regulative adjustment desired. Other things equal, a larger number of teeth affords correspondingly finer steps of adjustment. The teeth are such as to oppose the unwinding of the spiral spring 7. The interengagement between the respective teeth operates not only to prevent unwinding of the spring and turning of the sleeve or quill, but also holds thesleeve or quill in position on its pin or stud. This holding action may be additionally insured by forming the dog or latch 11 with a forwardly-directed end. Requirement of bolt ing or other auxiliary holding means to maintain the quill on its pin accordingly is obviated, and the construction is simplified, thereby greatly facilitating changing, cleaning, etc. The outer end of the sleeve or quill may be provided with some convenient grip for hand-turning; for instance in Fig. 1 it is slotted as at 13, to receive a screw driver or the like; and as will be readily apparent, by the application of such to the slots the sleeve or quill may be turned whereby to set the ratchet to desired tension. By arranging a pair of springs on corresponding sides of the bracket 4, uniformity ofpressure is furthered. V

In use, the brush is inserted in the guideway, and the spring 7 with its sleeve or quill is set on the supporting stud, with the brush extension 8 bearing upon the brush. The

ratchet is set to the desired tension. As the brush wears down and the tension correspondingl eases up, compensation may be readily had by turning the sleeve 9 with a screwdriver or the like, the ratchet teeth setting up correspondingly against the fixed pawl or dog. When it is desired to remove the spring for any reason, by turning the quill forward just enough to loosen the inter-engagement of the dog, the entire quill and spring may be readily removed from the supporting stud.

Other modes of applying the principle of the invention may be employed, change being made as regards the details described, provided the means stated in any of the following claims, or the equivalent of such, be employed.

I therefore particularly point out and distinctly claim as my invention:

1. A brush holder, comprising a guide-way, an external spring having an extension for coacting with a brush therein, a sleeve for said spring, and support-means for the sleeve, the spring-force retaining the sleeve against axial displacement therefrom without auxiliary end-obstructing means.

2. A brush holder, comprising a guideway, a spring coacting with a brush therein, and means in common for regulating the force of the spring and for holding the spring against lateral displacement, said means embodying a ratchet having axially-directed teeth.

3. A brush holder, comprising a support, a brush-receiving channel, a spiral spring for coacting with a brush therein, a mounting sleeve held in said spring by the frictional grip thereof, a stud upon which said sleeve is rotatable, and means coacting with said sleeve for controlling said spring.

4. A brush holder, comprising a support, a brush-receiving chamiel, a spiral spring for coacting with a brush therein, a sleeve carrying said spring, means upon which the sleeve is supported, and combined means for controlling the spring-tension and for retaining the spring 011 said sleeve-support means, including axially-directed ratchet teeth at the end of the sleeve.

5. A brush holder, comprising asupport, a bruslrreceiving channel, a spiral spring for coacting with a brush therein, av sleeve carrying said spring, a stud on said support for receiving said sleeve, and combined means for holding the sleeve on the stud and for controlling the spring-tension, said means including a fixed tooth on said support and ratchet teeth on the inner end of said sleeve.

6. A brush holder, comprising a support, a brush-receiving channel, a spiral spring for coacting with a brush therein, a sleeve carrying said spring, a stud on said support for receiving said sleeve, and interengaging teeth between the inner end of said sleeve and the support tending to hold the sleeve in position on the support.

7. A brush holder, comprising a bracket, a guide-way, a brush-receiving channel, a spiral spring for coacting with the brush therein, asleeve carrying said spring, a stud on said bracket for receiving said sleeve, a forwardlydirected fixed tooth on said bracket, and ratchet teeth on the inner end of said sleeve for coacting with said fixed tooth and holding the sleeve on the stud without auxiliary holding-means.

Signed by me this 23rd day of March, 1931.

ALEXANDER MORTON MacCUTCl-IEON. 

